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Sen.-elect Doug Jones, the Democrat from Alabama who beat Republican Roy Moore in last month's special Senate election, has tapped former Department of Transportation staffer Dana Gresham as his chief of staff, making him the only African-American chief of staff for a Senate Democrat.

"I would like to welcome Alabama native & former Asst. Secretary for Governmental Affairs at @USDOT Dana Gresham, who will be joining our team as Chief of Staff," Jones tweeted Tuesday.

Prior to working at the Department of Transportation under President Barack Obama, Gresham worked for Rep. Bud Cramer, D-Ala., and Rep. Artur Davis, D-Ala.

Dana Gresham was named on Jan. 2, 2017 by Sen.-elect Doug Jones, D-Ala., as his chief of staff.

The appointment follows pressure from several organizations representing various communities of color that asked Jones last month to hire at least one minority to a senior-level position.

Two Republican senators, though, Tim Scott of South Carolina and Jerry Moran of Kansas, reportedly have black chiefs of staff.

Seventeen organizations, including the NAACP, National Association of Latino Elected and Appointed Officials and the National Urban League, wrote a letter to Jones in December suggesting he hire a person of color in light of the lack of diversity among Senate staff. The Joint Center for Political and Economic Studies organized the effort and drafted the letter.

"As a new Member of the U.S. Senate, you have an opportunity to show your constituents that not only do their voices matter, but that their experiences and skills are vital to the work that you do to represent them," the groups wrote in the Dec. 19 letter to Jones. "Ensuring racial diversity among your staff would enhance the deliberation, innovation, legitimacy, and outcomes of your office and of the Senate as a whole. Hiring at least one person of color to your senior staff in Washington would speak loudly, and we ask that you do so among the qualified applicants that you will receive."

"Great News! Birmingham’s own stand out Dana Gresham chosen to be Chief of Staff to Alabama’s Senator Doug Jones!" tweeted Rep. Terri Sewell, D-Ala. "Looking forward to working with them to move Alabama forward!! @GDouglasJones."

Amanda Brown Lierman, political and organizing director for the Democratic National Committee tweeted, "Snaps for @GDouglasJones naming Dana Gresham as his Chief of Staff! #DougJones will be the ONLY #Senate #Democrat to have a black COS."

And Alpha Phi Alpha fraternity tweeted, "Congratulations to Brother Dana Gresham [Mu Lambda '97] for being appointed as Chief of Staff for Alabama Senator-elect, Doug Jones, who will be the only member of the Democratic caucus to have a Black/African-American chief of staff."